Researchers at a Birmingham university are developing a new "sticky liquid" drug which could result in easier treatment for patients suffering oesophageal problems.

A simple liquid formulation which sticks to the oesophageus wall could act as a drug barrier enabling conditions to be treated more effectively.

Scientists from Aston University showcased their research at the British Pharmaceutical Conference being held in Manchester yesterday.

Danielle Russell, of the university's medicines research unit, said: "There are several disorders of oesophageal movement, but, at present, no drug treatment targets the oesophagus directly.

"Bioadhesive formulations allow us to target drugs to a specific site.

"In theory, a good bioadhesive, when swallowed, will have prolonged contact with the inner oesophageal surface, allowing time for the drug to absorb into the relevant site." Treating oesophageal problems with drug therapies is often difficult because the body naturally reacts to clear the passage of food.

But Aston University's research team carried out a series of tests to examine how oil- in- water emulsions, designed to mimic the effect of saliva, were retained in the oesophagus.

They found the emulsions did indeed stick to the oesophageal tissue. Scientists then looked at whether adding drugs affected the solution's "stickiness".

Results showed that incorporating the drugs did not impair retention of the emulsions in most cases, and also that they were steadily released over a four-hour period.

Ms Russell said these findings would have several advantages for local drug delivery. She said: "A bioadhesive formulation could reduce the drug dose required because the drug is not diluted in the body fluids, as occurs with a systemic treatment. It also avoids inactivation by gastrointestinal enzymes.